New England Geophysical

Radiological

Measuring Radioactivity Levels in the Environment

The natural radiation in this New Hampshire granite outcropping was
measured at three times the natural background level. The scenery is
stunning but it would be better to build your house elsewhere.

Our world is radioactive and has been since it was created. Over 60 radionuclides
(radioactive elements) can be found in nature. They can be placed in
three general categories:

Radionuclides are found naturally in air, water and soil. They are even found in us,
being that we are products of our environment. Every day, we ingest and inhale
radionuclides in our air, food, and water. Natural radioactivity is common
in the rocks and soil that make up our planet, in water and the oceans, and
in our building materials and homes. There is nowhere on Earth that you
can not find natural radioactivity.

High Background Radiation Areas

Background radiation levels are from a combination of terrestrial (from the 40K,
232Th, 226Ra, etc.) and cosmic radiation (photons, muons, etc.). The level is
fairly constant over the world, being 5-10 µrad/hr. Around New England though,
there are some areas that have higher background radiation levels. In some areas
of New Hampsire, around granite outcroppings for example, we have measured
natural radioactivity levels that are 4 to five times Background. The higher
radiation levels are generally due to higher concentrations of radioactive
minerals in both the soil and rock.

Historical

The "red" in this 6" saucer is uranium oxide. This plate
was made in 1938 when uranium oxide was used in the
manufacture of pottery glazes.

The mineralogy of some radioactives - uranium for example - is very interesting.
The native American tribes, such as the Navajo, Ute and Apache used the bright
colored secondary uranium minerals to paint their faces. The first industrial use
of uranium was as pigment in the glass and pottery industries.
Tens of thousands of these plates and saucers were made. Many are still available
today at antique shops - see photos - the rest are in landfills.
Then in the early days of the 20th century Marie Curie discovered a new
element - radium - in uranium ores. This light emitting element was used in
medicine and in phosphorescent watches of the day. During the second
world war uranium got its present day use in the nuclear industry. Uranium
ores, regarded as useless by miners for centuries, suddenly became a
strategically important ore.

..

Depleted uranium was mixed into the glass for this cup.
Under a UV (Blacklight) the cup gives off an erie glow.
This style of glassware was popular during the 1950's

Today, a curious balance has been struck between usage and the known
hazards of radioactive materials in our environment. Awareness and
monitoring of the radioactive levels in our environment is a critical part of
this balance.

New England Geophysical is able to conduct radiological field surveys
of landfills, site contamination, buildings, or geologic outcroppings,
at any location in New England.

We are also suppliers of calibrated radiological samples for research and education.
Please contact us for details and availability of radiological samples.

The following are naturally occuring radioactive samples collected during field surveys from around the USA**

		Autunite A minor ore of uranium. Its green and yellow color shades seem to glow and are actually fluorescent. The crystal aggregates look like inflated mica and are distinctive. The structure is composed of phosphate tetrahedrons linked to uranium-oxygen groups that form distorted octahedrons. The phosphates and uranium groups lie in sheets that are weakly held together by water molecules. This structure produces the tabular habit, the one perfect direction of cleavage, and the relative softness.
		Dumontite Dumontite is a rather rare lead-uranyl-phosphate. It occurs as pale to deep yellow minute crystals and shows a weak green fluorescence. This naturally occuring radioactive ore must be handled cautiously.
		Ellsworthite This is one of the tantalum/niobium oxides that are generally difficult to distinguish. It crystallizes in the isometric symmetry class and forms fine octahedral crystals that are typically and characteristically modified by other isometric forms. Ellsworthite generally contains substantial amounts of radioactive elements called rare earths producing the radioactivity. It is found in a rather unusual igneous rock called a carbonatite (which is composed mostly of calcite), alkalic pegmatites called nepheline syenites, and in granitic pegmatite dikes.
		Soddyite Soddyite is a yellow mineral, first discovered in the Shinkolobwe mine, Shaba DRC. Mostly, Soddyite forms prismatic crystals, which can be opaque or transparent. Some crystals are even transparent with opaque bands. Naturally occuring, highly radioactive, deposits of Soddyite must be handled with caution.
		Torbernite Torbernite is a rare copper-uranium-phosphate mineral. Because it contains uranium, it is a “hot” (radioactive) mineral that must be handled cautiously. Though the crystals share the thin, tabular shape of autunite and some other uranium minerals, torbernite does not fluoresce. The green color is also different from most uranium minerals.
		Uraninite Uraninite occurs in granitic magmas. When these magmas solidify uraninite will occur in granite or granite-pegmatite. After this phase water often remains with solutions of quadrivalent uranium. These solutions will also deposit uraninite. This is called a hydrothermal formation. The uranium from the granitic rocks and their hydrothermal systems will find its way in other geological settings. It can end up in sedimentary and metamorphic rocks.
		Urano-humate This is a fine example of a limestone matrix mostly saturated with black Urano-Humate, an organic uranium compound created when Humic Acid ( derived from decaying plant material ) mixes with downward percolating rainwater. As it moves through subsequent rock it then chemically leaches naturally occuring traces of uranium and concentrates it in classic "roll-front" ore bodies.

** These images have been presented for educational value only.
No attempt should be made to identify natural radioactive ores
based upon these images.

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